Steven Pinker’s The Better Angels of Our Nature, a book published in 2010 which posits that the world is in fact becoming better and less violent, skyrocketed to No. 1 on Amazon this week after Microsoft founder Bill Gates gave it a glowing recommendation in a series of tweets directed at recent graduates.

Gates’s tweets, sent Monday, gave advice to graduates on industries to look into when starting out, and how to measure happiness. The statement culminated in the shoutout for Pinker’s book, which Gates said he would give to each student as a graduation present if he could, calling it “the most inspiring book I’ve ever read.”

9/ If I could give each of you a graduation present, it would be this–the most inspiring book I've ever read. pic.twitter.com/P67BuvpELJ